Effects of current densities,WC content,pH value and deposition temperature on the index,such as coating hardness and surface appearance were studied. The optimum operation condition was determined by orthogonal experiment:the current density is 7 A/cm2,the temperature is 50 ℃,the WC content 20 g/L,pH value 5.0 with ultrasonic concussion. Under this condition the optimal hardness and surface appearance could be obtained. Meanwhile the hardness,oxidation resistance,corrosion resistance and the surface struct...